California: Sacramento-San Joaquin Delta

99 Coastal Destinations Rated: Facing Trouble

Small towns with an early 20th-century ambience dot central California's spindly network of rivers and canals. More than a century's worth of water drainage projects have left much of the region below sea level. The fragile, worn-out levee system threatens to give way and cause catastrophic flooding if it is not upgraded soon.

Here is a representative sampling of additional anonymous comments from the panelists. They are not necessarily the views of the National Geographic Society:

"The area retains considerable charm, and efforts to preserve the wetlands have had good results. The built heritage consists of farms, rice fields, dikes, berms, and small towns constructed during the late 19th and early 20th century."

"Plays an extraordinarily important role in California's environment, infrastructure, and economy. The whole complex—ecosystem doesn't seem like the right term—has been dramatically altered and is extremely vulnerable to earthquakes and climate change. Much of it is below sea level due to subsidence. The system will not be sustainable without major human intervention."

“Lack of investment in berm infrastructure may lead to flooding or other catastrophes."